Antagonistic Regulation of ABA and GA in Metabolism and Signaling Pathways

Abstract

The phytohormones gibberellic acid (GA) and abscisic acid (ABA) are widely recognized as essential endogenous regulators that mostly play antagonistic roles in plant developmental processes and environmental responses. A variety of both internal and external cues oppositely regulate GA and ABA biosynthesis and catabolism, which directly and indirectly affect their signaling pathways and subsequent responses. Recent discoveries have revealed direct molecular links between GA- and ABA-signaling components, which provide novel insights into their antagonistic regulation. In this review, we mainly focus on these recent reports and the growing understanding of GA and ABA antagonism in metabolic regulation and signaling interactions, and attempt to clarify the problems and challenges involved in exploring the complicated regulatory events associated with these two phytohormones.

Endogenous gibberellins and abscisic acid-metabolites: their role for during flower bud abscission and embryo development in pistachio

“…Some researchers suggested that the competition between flower buds and food for fruit and assimilates is responsible for this phenomenon (Cetinkaya, 2004;Ulger et al, 2004;Baninasab et al, 2006;Mirsoleimani et al, 2014) while others stated that unbalanced nutrition was not the main cause of the inhibition of flower bud formation, and more attention should be paid to the hypothesis of PGRs (Baktır et al, 2004;Gomez-Jimenez et al, 2010;Vemmos, 2010;Gundesli et al, 2019). In higher plants, ABA and GA antagonistically regulate various physiological growth periods, including seed dormancy, seed germination, root growth, shoot elongation, leaf development, flowering, flower bud formation, abscission, and fruit development, as well as biotic and abiotic stresses (Vanstraelen and Benková, 2012;Liu and Hou, 2018). ABA was first isolated from the mature flowers of cotton, rose, peas, and fruit as an abscission accelerator (Lui and Carns 1961;Mayak et al, 1972;Ehuwens and Schwabe, 1975).…”

A matter of life and death: Molecular, physiological, and environmental regulation of seed longevity

“…Phytohormones play key and distinct roles throughout the lifecycle, including seed dormancy, germination, and abiotic stress responses (Liu et al, ; Liu & Hou, ; Shu et al, ; Shu, Liu, Xie, & He, ; Shu, Zhou, Cheng, Luo, & Yang, ). It is widely recognized that ABA and GAs mediate seed dormancy and germination antagonistically (El‐Maarouf‐Bouteau & Bailly, ; Jeevan Kumar et al, ; Shu et al, ; Shu, Zhou, & Yang, ).…”

An ABA-GA bistable switch can account for natural variation in the variability of Arabidopsis seed germination time

“…However, there is a large 2 body of work using percent germination as a measure of seed dormancy. A number of quantitative In-depth molecular studies have shown that the decision to germinate is controlled by the balance 9 between two hormones, gibberellic acid (GA), which promotes germination, and abscisic acid (ABA), 10 which represses it (Liu and Hou, 2018). These hormones function in a mutually antagonistic manner 11 by each inhibiting the synthesis and promoting the degradation of the other (Liu and Hou, 2018;12 Piskurewicz et al, 2008).…”

“…A number of quantitative In-depth molecular studies have shown that the decision to germinate is controlled by the balance 9 between two hormones, gibberellic acid (GA), which promotes germination, and abscisic acid (ABA), 10 which represses it (Liu and Hou, 2018). These hormones function in a mutually antagonistic manner 11 by each inhibiting the synthesis and promoting the degradation of the other (Liu and Hou, 2018;12 Piskurewicz et al, 2008). Additionally, the two hormones have opposing effects on downstream 13 transcriptional regulators that control the balance between dormancy and germination (Liu et al, 14 2016; Piskurewicz et al, 2008;Shu et al, 2013).…”